


More to Expect when...

by Astoria Gracewell (arh581958)



Series: What to Expect (an ABO series) [2]
Category: Mortal Instruments Series - Cassandra Clare, Shadowhunter Chronicles - All Media Types, Shadowhunter Chronicles - Cassandra Clare, Shadowhunters (TV)
Genre: Alpha!Magnus, Alpha/Beta/Omega Dynamics, Anal Fingering, Anal Sex, Body Worship, Domestic, Domestic Fluff, Fluff, Fluff and Smut, Gratuitous Smut, Lactation, Lactation Kink, M/M, Male Lactation, Mpreg, Omega!Alec, Pregnant Sex, Pregnant!Alec, Romantic Fluff, Shameless Smut, Smut, Tooth-Rotting Fluff, Weight Gain, anal penetration, body issues, self-confidence issues
Language: English
Status: Completed
Published: 2016-06-08
Updated: 2016-06-08
Packaged: 2018-07-13 01:41:54
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,026
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7133414
Author URL: https://archiveofourown.org/users/arh581958/pseuds/Astoria%20Gracewell
Summary: <blockquote class="userstuff">
              <p>... your mate is about eight months along. That, of course, means that Alec's extra self-conscious about all the weight he's gained over the pregnancy. No one will ever accuse Magnus of not being a good mate. He worships the ground that his omega walks on.</p><p>(Or: Pregnant Sex in A/B/O verse because reasons part ii)</p>
            </blockquote>





	More to Expect when...

**Author's Note:**

> Following up from the first one, Alec is now on his 3rd trimester and it comes with a few more pounds than he expected. Written for prompt on tumblr, anonymous wanted bodyshy!Alec and a loving!Magnus. Please enjoy~ For anyone who reads, Religious Obligations, it's not forgotten I promise. I just need to unclog my brain before I start writing again. Hugs and Kisses! 
> 
> **Warnings:** This story contains _MPREG_ in the A/B/O universe. If you are uncomfortable with the theme, I respectfully suggest that you turn back now because this will sear through your eyeballs and melt your brain into mush. I do not have the money to be held responsible. Also contains book spoilers. Thank you.
> 
> Not Beta Read.

Alec waddled—yes, waddled, because that’s how he pretty much got around these days—to the bathroom. He felt _huge_ , eight-month-old stomach protruding with their unborn baby. Most days, he needed to lean against the wall for support in order to get around.

Magnus has been more than careful with him—bending to his every will since he reached the third trimester, be it bubbles baths, massages, or food, any and all types of door that he craved.

It came to no surprise that he _grew_ , stretching out his old threadbare pullovers and sweatpants in ways that his clothes would never recover from again.

Alec entered the bathroom and stared at his round face in the mirror. He groaned, not liking what he saw at all. His hand rested on his middle. He used to have abs, which according to Magnus, looked like they’ve been sculpted by the gods. Now, he had spidery-white stretchmarks all over his belly.

His mid-section wasn’t the only one which softened with the pregnancy. His face, his arms, his pecs, his legs, and his ass all fell victim to his unhealthy and illogical nightly cravings. Magnus denied him nothing, giving into each and every single one with wanton joy.

“Alexander?” His mate’s voice caught him by surprise. Magnus stepped up behind Alec, covering the omega’s hand with his. “Is something wrong?”

Alec hadn’t realized that he was staring. “It’s nothing. I was just going to piss.”

“You’ve been here for twenty-minutes, Alexander. Are you sure there’s nothing else?” Magnus’ golden green cat-like eyes met Alec’s deep blue ones in the mirror. He placed a tender nip on the back of Alec’s nape, at the scruff, for comfort. “You know you can tell me everything, right?”

“Yeah,” Alec answered but the quietness in his voice spoke volumes. He gently pushed Magnus off. “I’m gonna piss now. Or are you going to stand there and watch me too?”

On a normal day, Magnus would have risen to the bait and eagerly teased his Shadowhunter but today he didn’t. “Alright. Food’s only going to be a minute more. Come to the table when you’re done, okay?”

“Okay.”

Alec took it as a sign that Magnus no longer liked seeing his body.

***

That night, Alec insisted on taking a bath alone instead of the nightly rub-down which they’ve grown accustomed to since he reached his second trimester.

Magnus said nothing and gave him space.

***

Their bedroom changed completely by the time he came out of the bathroom. Small fluorescent jars floated lazily around the room, glowing in soft orange. Soft music played in the background. Dark blue and purple flowers spread on top of their bed, contrasting to the canary yellow sheets.

Alec smelled his alpha before Magnus spoke. Two hands crept around his round belly.

“Did you enjoy your bath?” Magnus asked, with lips teasing Alec’s ear. He stepped closer to his half-naked mate. He moved closer in until bare his chest pressed against Alec’s back. Warm and cool, the perfect contrast.

Alec leaned into the touch. “I did. Thank you for preparing it for me.” He spoke about the magically warm water infused with calming hers and bath salts. He turned to face Magnus. “But I don’t understand what all _that_ is all about.”

Magnus nuzzled Alec on the cheek. “It’s for you, sweet-cheeks, I intend to take you apart tonight and make you scream.”

“M—Magnus!” Seven years together and he still wasn’t used to Magnus’ smooth-talking. “I—I can’t, it’ll be hard to move…”

“Worry not, my love.” Magnus kissed him on the cheek. “All you have to do is lie down and let me do all the work. Let me worship you, Alexander, the way you should be worshipped, the way I’ve always wanted to worship every single part of your body from the day we met. Will you let me?”

Alec bit his lip, contemplative.

Magnus folded onto his knees in front of his mate, close but not touching, face angled just right to kiss the bottom of Alec’s stomach. He gazed up, eyes staring at Alec with reverence.

“Alexander?” He called out as a question.

“Yes,” Alec agreed, closing the gap between them, pressing his pregnant belly against Magnus’ face. The pup inside him recognized its alpha-father and kicked for joy. He couldn’t help but giggle when a well-placed kick landed right on Magnus’ cheek.

“He’s a strong little guy, isn’t he? Just like his Shadowhunter daddy.” Magnus mused while he rubbed his sore cheek. “He’ll be kicking demon-butt in no time.”

“Take me to bed, Magnus.” Alec touched Magnus on the shoulder, and tugged the alpha off the floor. “I’m too heavy and pregnant for floor sex.”

Magnus laughed as he led them to bed.

“Lie down. On your back. Get as comfortable as you can.”

Alec shimmied to the edge of the bed, legs spread, pillows supporting his back and hip. The towel carelessly fell away mid-shimmy, leaving the long trail of his creamy white legs lead to the center of his being. Other times, he would have felt shy about being laid out, fully exposed like this, but Magnus’ eyes held a feral glint.

He felt wanted, needed, and loved.

“Come on, alpha,” he challenged, widening his stance. “Show we what you got.”

Magnus growled—low, deep, and rumbling down to the tips of his toes. With a snap of fingers, his clothes disappeared then he cat-crawled his way up the bed. “Come here, Alexander,” he practically purred against Alec’s lips, “I want to taste you.”

Their lips met in chastely intimate kiss. No tongue. Just skin on skin, but already the tension between their electrified with lust.

Alec moaned as Magnus’ large alpha cock bumped against his belly. Slick dripped out of his hole, and was sure to leave another stain on their sheets but he couldn’t help himself. He couldn’t stop it. _Want_ flooded through his system like a genial wave, coaxing him into descent.

Then, in an instant, Magnus was gone.

“Whu—what?” He blinked, looking for his mate.

“I’m here, Alexander.” A touch to his ankle told him everything.

Alec propped up to his elbows to see Magnus kneeling at the end of the bed, between his parted legs, bowed over his feet. He wiggled his toes for attention. “Are you going to give me the foot rub I missed in the bath?”

“That depends.” Magnus lifted a foot to kiss the arch tenderly. “Do you want a foot rub, _Alexander_?” He traced the instep with his nose, and dragged the foot until the pad of the big toe rested over his lips.

No stranger to this sort of play, Alec pushed his toe between Magnus’ lips, moaning when he felt the too-hot too-wet too-naughty suckle of his mate’s mouth. “Touch me, Magnus, please, I don’t care how, just…” He reached out, suddenly craving for the warlock’s touch. Magnus reached out his hands to that their fingers laced together.

“Just touch me,” Alec craned his neck to watch but eventually it started to ache. Panting, he collapsed on his back, big belly obscuring his view but can _feel_ every single one of Magnus’ touches. He let out a hiss of annoyance as he flopped on the bed.

“Something wrong?”

“It’s nothing.”

“Alexander,” Magnus warned, while he slipped his tongue between Alec’s toes, earning a sigh of pleasure from the Nephilim. “We need to talk about these things. You can’t keep shutting me out.” He sucked heavily on the pinky-toe, making Alec whimper. “Alec, please, tell me what’s wrong?”

Alec threw his head back with a sigh, defeated but impossibly horny from the pregnancy and the fact that he made currently resided between his parted legs. “I—” he hid his face under his crossed arms, turning his head to the side, looking away even if he can’t see beyond his belly. He still felt embarrassed. “I’m… _fat_ , how can you even want me?”

Magnus crawled over him again, slightly to one side. He could feel his mate’s erection dragging across his skin in a sinful delight. Goosebumps rose where the silky precum glistened. Magnus looked him in the eye, intense golden green cat-like eyes staring at him affection, warmth, and reverence. A hand came to rest on his cheeks.

“I had so many plans for you tonight, my Alexander,” said Magnus, as he gently stroked Alec’s face, “but perhaps what I wanted would have to wait another time.” He pressed a sweet kiss on Alec’s lips, tongue darting out to trace the seam. Alec opened his mouth instinctively.

Magnus licked into his mouth, slow and sensuous, pouring so many emotions into the kiss that Alec’s chest filled with it. They made love with their mouths, breathing through the noses, not wanting to break the kiss. Lips locked. Noses brushed at the tips. Foreheads pressed against each other.

Soon, they were panting open-mouthed face-to-face. Alec chased Magnus’ lips.

“You are gorgeous, Alexander,” Magnus murmured into Alec’s lips. The other opened his mouth to complain but Magnus shushed him with another kiss. “No, this time, you listen to me, Alexander. You will accept every praise—” a kiss on the check, “—every word—” on the nose, “—every ounce of love that I’m giving you right now—” on the forehead.

Alec’s eyes fluttered open. He wasn’t even aware that they closed.

Magnus smiled. “Because you are carrying out _first_ child, and you’ve made me even move happier than when we mated. We’re making a life together, Alexander, a life that is ours to hone and cherish and watch prosper. So let me love you.”

“Okay,” Alec answered breathlessly, nodding, “okay, just please…” He didn’t even know what he was asking about.

Magnus nosed at Alec’s neck, taking in the smell of _happy pregnant_ omega and purring. “I love you,” he said, licking the pale creamy ear shell. “I love all the sounds that you make, Alexander, so let me hear more of it.”

“Magnus, please, Magnus…” Alec’s toes curled into the sheets. He couldn’t think any more. His words sounded nonsense to his ears but he kept speaking, talking, babbling in incoherence while Magnus revered his body.

Magnus licked his neck, all over the side and down to the collar where their mating bite lay. He nipped and sucked over the long-faded pale scar. Their bond tingled, sending wave after wave of pleasure zinging through Alec’s skin.

“Are you wet for me love?” He rubbed the outside of Alec’s thighs, teasing.

“Yes,” Alec groaned as he parted his leg even more, knee bent, exposing his hole as another wave of slick thickened the stain on their bedspread. “So wet, Magnus, so wet for you, _alpha_.”

Magnus moved to the inner thigh, keeping his strokes gentle but steady. “I believe you. I can smell it. I can smell your sweet omega slick _begging me_ to knot you, my love, my Alexander.” He didn’t stop the kisses down Alec’s enlarged pecs.

Alec sobbed when a finger brushed over his swollen hole. “Magnus, your finger, please.”

“No.”

His eyes shot open to see his mate smirking down at him. He grabbed Magnus’ bicep, not knowing what else to do, eyes saying everything that his mouths couldn’t.

Magnus licked a wet line from the base of his throat to his chin.

“I’m not going to make love to you until I’ve wiped away every shred of doubt in your system of how much I _want you_ , Alexander, pregnant or not pregnant, in heat and outside of heat, on your back or on all fours, when you’re angry or your sad— _I will always want you_.” For a moment, his eyes flashed alpha-red.

“Come here,” Alec growled, hand gripping Magnus by the hair and pulling the alpha for a kiss. The kiss was wet and sloppy. Saliva ran down their chins by the time it ended. Alec wasn’t done. He yanked Magnus by the hair down to his nipple. “Suck,” he ordered.

“Ohh, Alexander, you know I love it when you get—”

“Suck my tit, Magus, or I swear to the angel, I’m going to the bathroom and finishing this myself.”

They both knew it was a weak threat. Alec barely had enough balance to walk to the bathroom, let alone have enough to finger-fuck himself. Magnus relented either way, kissing down the pale expanse of his omega’s naked flesh. He lowered his lips over Alec’s right nipple and started his suckling.

“Hmmm,” Alec moaned as the pressure on his tit alleviated. On the seventh month, he began lactating for their future child, and Magnus volunteered to suck the milk from his tit after the omega started complaining of chest pains. They suckled every other night but with Magnus’ increased clients as of late, they haven’t been drained in three days.

“More, Magnus, keep doing that.”

Magnus added a little tongue and teeth to his repertoire, making Alec arch his back.

Alec lost his mind. A tongue swirled around his swollen nub and a finger around his pulsating hole. He lost himself to the delirium of dual pleasure that Magnus coaxed from his body. He panted and writhed and chased the pleasure on both sides. “Magnus, Magnus, Magnus.”

“That’s it, Alexander.” Magnus encouraged. “Take your pleasure, my love, trust me.” 

Alec did.

Magnus peppered his swollen breasts with kisses after both were drained. Raining kisses down every inch of skin from Alec’s collar bones to the top of the protruding stomach. Then, Magnus spread his hands, slick-soaked and dripping, all over the round flesh. It felt wrong and dirty but Alec felt a dribble of precum escape him.

“Oh, Magnus, Mag—Magnus!”

Once his stomach shined with his own slick, he watched under half-lidded eyes as his alpha, mate, and lover, kissed his belly button. “Oh Magnus!” His toes and fingers curled into the canary yellow sheets, as he tried to push into the touch. “Please, please…”

Achingly slow, Magnus cleaned up the messy slick with his tongue, tracing every single path of the stretch marks, every branch and crevice, until the alpha’s scent covered Alec’s entire belly.

“Oh, angels!” Alec yelled when two stealthy fingers suddenly poked his prostate. He didn’t even realize when Magnus squirmed the digits passed his hole. They stretched him, opened him, prepared him for the big alpha knot that was to come. He shuddered in anticipation. “Yeah, yeah, just like that, just like that, Magnus, please, more.”

He didn’t even realize that Magnus had moved again until, “Oh,” he moaned out so loud that it surely woke a few neighbors. He struggled to crane his head to see Magnus’ dark black hair with purple highlights bobbing in-between his legs, mouth on his flesh and swallowing him hole. He knew his cock was bigger than the average omega’s but Magnus’ went down like a champ, gag-reflex all but forgotten.

Alec curled his legs over Magnus’ shoulders and squeezed. It earned him a pinch on a softer round ass-cheek, and he yelped.

“Magnus, come on, I’ve been ready since you fingered me. Please, please, I need your cock, _alpha_. I want it.”

Magnus chuckled against his thighs. The sound traveling like a feather-light touch straight to his groin. Alec felt like his orgasm punch through him without warning, pouring out of him in pulses, while Magnus greedily drank his spend. He fell boneless against the bed, too tired got anything else.

“Damnit!” He cursed, one of the rare occasions that he did, “How’re you gonna fuck me now?” He complained while staring up at the ceiling in embarrassment.

“I can think of something.” Magnus confidently pecked small butterfly kisses up his thigh, over his round stomach, on each nipple, until finally reaching his lips. “I can always love you soft, Alexander, you’re especially loose-limbed after you’ve come. I would very much like to bury my knot inside you and wait until you get hard again.” He nosed Alec affectionate on the jaw. “Think you’re up for round two, my love?”

Alec hummed and wrapped his arms around Magnus’ shoulders.

That was answer enough.

Magnus inched in but had to pull away to avoid crushing their baby. He kept their hands over Alec’s belly while he sheathed inside his omega, murmuring praises and promises of eternal love and affection. Sweat beaded off their skins. The scent of sex filled the air. Neither of them needed to speak when they were connected so intimately.

It lasted for a long time.

“Magnus,” Alec panted while Magnus jerked his cock slowly. It could have been an hour, or two, he didn’t really know anymore. Somewhere in the haze of lust, Magnus coaxed him to hardness again and his second orgasm curled like a fire inside his gut. “I’m gonna cum soon. We need—we need to change positions—can’t—can’t not like this—we’ll—we’ll crush the baby.”

Magnus’ mewled in disappointment but the paternal instincts overrode his lust. He gently shifted them on their sides, his front to Alec’s back, lifting Alec’s leg with an elbow under the knee. He slid inside against, faster this time, well-aimed at the prostate.

“Do you wanna jerk yourself off or should I?”

In answer, Alec hooked his arm under his knee. Magnus got to work immediately.

The room filled with Alec’s wanton moans. “Magnus, Magnus, Magnus! Please, please, let me cum, let me cum, I wanna—I wanna—ohh!”

Alec saw stars when his second orgasm hit, and seconds later Magnus followed him. Hot stripes of cum painted the sheets while Magnus painted his insides, filling him with another load over very potent alpha semen while he carried their first child to full term. Their bond sang in joy. It filled with him to the brim, causing his eyes to spill.

Magnus scented the salty tears. “ _Alexander_ , are you alright?”

“Yes,” Alec whispered, angling in for a kiss, “It’s just overwhelming how much you love me.”

Magnus smiled into the kiss, knot trying them together and hand drifting to curve protectively over Alexander’s belly. “I love you very much, Alexander.”

Alec pressed their lips together, sealing the promise of tomorrow with another kiss.

**Author's Note:**

> If you have a prompt or an idea, you can [INSPIRE ME](http://arh581958.tumblr.com/submit) on tumblr. Or [TALK TO ME](http://arh581958.tumblr.com/ask)~
> 
> As always, **kudos/comments/bookmarks** are all appreciated by this author. I take comments as extra-kudos and I _do_ read the bookmark tags (some are really fun).


End file.
